How to convert .dat, .lvl, and premium Minecraft worlds?

[115Predator]

How does one convert a classic Minecraft map to a premium Minecraft world?

 

[Wimali]

You can import .dat files into MCedit and then export that MCedit world.
http://www.minecraftforum.net/topic/789562-convert-classic-worlds-to-beta/
http://lmgtfy.com/?q=convert+classic+maps+to+premium

 

[zezmi]

Jusr do what Bram says, he's leading you down the right road. If you hit a bump just ask about it. (No use in toiling around for an hour about something we could explain and you could finish in 5 minutes).

 

[Amorix]

You create a time paradox.